diff --git a/src/DxfScene.js b/src/DxfScene.js
index bece9c4..5d21c64 100644
--- a/src/DxfScene.js
+++ b/src/DxfScene.js
@@ -835,6 +835,7 @@ export class DxfScene {
                     indices.push(0, 1, 2)
                 } else {
                     indices.push(1, 2, 3)
+                    indices.push(2, 3, 0)
                 }
                 _vertices.push(v3)
             }